Activation of T-regulatory cells by a synbiotic may be important for its anti-inflammatory effect

Excerpt

We read with great interest Moser and colleagues’ paper entitled “Effects of an oral synbiotic on the gastrointestinal immune system and microbiota in patients with diarrhea-predominant irritable bowel syndrome” published in your journal [1]. The results showed that the synbiotic reduced the symptoms of irritable bowel syndrome (IBS) with increased microbiota diversity and decreased inflammatory status. The synbiotic increased butyrate, a key anti-inflammatory metabolite produced by intestinal commensal bacteria and decreased zonulin, an indicator of intestinal permeability. However, regulatory T-cells (T-Reg cells) changes by the synbiotic were not observed in this study although CD4 T-cells were significantly decreased. As activation of T-Reg cells by butyrate plays a key role in the intestinal inflammatory status [2], it would be interesting to further investigate the reasons as to why they were not altered in this study. We think that this may be related with a pre-existing dysbiosis in IBS; the dysbiotic intestinal microbiota results in reduced efficacious production of butyrate with a concomitant increase in lipopolysaccharide (LPS) translocations from the intestinal lumen to the mucosa. …